The number of reported cases of sexual activity involving a child under 16 in Surrey has quadrupled over the last five years, latest government statistics have shown.

The number of such crimes has increased from 31 in 2012/13 to 145 in 2015/16, according to figures released by the Office for National Statistics (ONS) last week.

An NSPCC spokesman said: “Recent investigations have exposed a dark underbelly of abuse that went on for far too long with the impact only now becoming tragically clear.

“Sexual abuse has a devastating impact on a child, and we urge all victims to come forward as soon as possible so they can get the support they need and offenders can be brought to justice.”

A spokesman from Surrey Police said the rise of reported cases reflected a willingness of victims to speak out.

The force works alongside NHS England, Surrey County Council, the Office of the Police and Crime Commissioner (PCC) and other statutory and non-statutory partners to provide support for victims.

Surrey Police also works with the Crown Prosecution Service to build cases against alleged attackers, and has specialist officers who support victims throughout the criminal justice process.

A spokesman for the force said: “Surrey Police takes sexual offences against children and young people extremely seriously and this remains a priority for Surrey Police, with the latest figures demonstrating the increasing level of confidence from victims to come forward.

“Over recent years Surrey Police has invested significantly in putting victims, who have often been through traumatic experiences, at the centre of the investigative process.

“The Force will always treat the welfare of victims as paramount and provide full support through the investigation and any subsequent prosecution.”

To report a sexual offence, call Surrey Police on 101 or report it online at http://www.surrey.police.uk/contact-us/report-online

The NSPCC advises victims to call Childline on 0800 1111.